Fixed Inductors

Part Number	Description / PDF	Quantity
CR43NP-180MC Sumida Corporation	FIXED IND 18UH 740MA 338 MOHM	0
0315CDMCCDS-1R0MC Sumida Corporation	FIXED IND 1UH 4.3A 41MOHM SMD	3000
5598 821 34 00 Sumida Corporation	FIXED IND 820NH 75MA 5 OHM SMD	0
CR43NP-220MC Sumida Corporation	FIXED IND 22UH 680MA 378 MOHM	0
RCH895NP-102K Sumida Corporation	FIXED IND 1MH 220MA 1.84 OHM TH	0
CDRH124NP-820MC Sumida Corporation	FIXED IND 82UH 1.3A 260 MOHM SMD	0
CDH115NP-560KC Sumida Corporation	FIXED IND 56UH 1.28A 140 MOHM	0
CDRH125/LDNP-220MC Sumida Corporation	FIXED IND 22UH 3.28A 44 MOHM SMD	2001
CD30D22HF-5R6MC Sumida Corporation	FIXED IND 5.6UH 1.35A 153 MOHM	0
CEP125NP-2R5MC Sumida Corporation	FIXED IND 2.5UH 15.5A 3.4 MOHM	0
CR32NP-270KC Sumida Corporation	FIXED IND 27UH 405MA 660 MOHM	0
CDEP134NP-0R6NC-H Sumida Corporation	FIXED IND 660NH 17A 2.5 MOHM SMD	40
CDRH73NP-121MC-B Sumida Corporation	FIXED IND 120UH 490MA 890 MOHM	0
CDH2D09BNP-100MC Sumida Corporation	FIXED IND 10UH 470MA 588 MOHM	0
CDRH104RNP-271NC Sumida Corporation	FIXED IND 270UH 470MA 1.07 OHM	0
CDRH4D18NP-330NC Sumida Corporation	FIXED IND 33UH 320MA 694 MOHM	0
CEP125NP-1R5MC Sumida Corporation	FIXED IND 1.5UH 16.5A 2.5 MOHM	0
CDRH70D45BT150NP-221MC Sumida Corporation	FIXED IND 220UH 910MA 550 MOHM	2000
CR54NP-820KC Sumida Corporation	FIXED IND 82UH 580MA 600 MOHM	0
CDRH2D14NP-4R7NC Sumida Corporation	FIXED IND 4.7UH 1A 169 MOHM SMD	0

Fixed Inductors

1. Overview

Fixed inductors are passive electronic components designed to store energy in magnetic fields when electrical current flows through them. Unlike variable inductors, their inductance values remain constant during operation. These components play critical roles in filtering, signal processing, energy storage, and electromagnetic interference (EMI) suppression across modern electronics, including power supplies, communication systems, and automotive electronics.

2. Main Types and Functional Classification

Type	Functional Characteristics	Application Examples
Wirewound Inductors	High precision, high current handling, low resistance	Power supplies, DC-DC converters
Chip Inductors	Compact SMD package, stable performance at high frequencies	Mobile devices, RF circuits
Ferrite Bead Inductors	Effective high-frequency noise suppression	EMI filtering in digital circuits
Thin-Film Inductors	Ultra-compact, high Q-factor, tight tolerance	5G communication modules, IoT devices

3. Structure and Composition

Typical fixed inductors consist of:

Magnetic Core: Made from ferrite, powdered iron, or composite materials to concentrate magnetic flux
Coil Structure: Copper wire wound around the core (enamelled or silver-plated)
Encapsulation: Molded resin or ceramic coating for mechanical protection and insulation
Terminations: Solder-coated ends for PCB mounting (for SMD types) or leaded connections

4. Key Technical Specifications

Parameter	Description	Importance
Inductance (L)	Measured in henrys (H), determines energy storage capacity	Defines filtering/energy storage performance
Rated Current (I_rated)	Maximum DC current before saturation	Prevents core saturation and failure
DC Resistance (DCR)	Resistance of coil windings	Affects efficiency and thermal performance
Self-Resonant Frequency (SRF)	Frequency where inductor behaves as capacitor	Limits effective operating frequency range
Q Factor	Quality factor indicating efficiency	Higher Q = lower energy losses

5. Application Fields

Consumer Electronics: Smartphones, laptops, LED drivers
Industrial Equipment: Motor drives, power inverters
Automotive Systems: ECU modules, EV battery management
Telecom Infrastructure: Base station filters, optical transceivers

6. Leading Manufacturers and Products

Manufacturer	Representative Product	Key Features
Murata	LQH3NPN100M	10 H, 1.2A, 1.8 1.4mm chip inductor
TDK	MLZ2012A100T	100MHz SRF, 1.0 1.25mm for RF circuits
Vishay	IHLP2525CZER1R0M	1 H, 12A, composite construction
Coilcraft	0402DC-103J	10 H, 5% tolerance, ultra-low profile

7. Selection Guidelines

Key considerations during selection:

Calculate required inductance based on switching frequency and ripple current
Verify rated current exceeds maximum operating current by 20-30%
Select SRF higher than circuit operating frequency
Consider package size vs. thermal dissipation requirements
For EMI suppression: Choose ferrite beads with impedance curves matching target frequencies

8. Industry Trends

Current development trends include:

Miniaturization: Sub-0.5mm size inductors for wearable devices
High-Frequency Operation: Components supporting >10GHz 5G applications
Integrated Solutions: Combined inductor-filter modules
Material Innovation: Nanocrystalline cores for higher saturation flux
Automotive Focus: AEC-Q qualified parts for EV/HEV systems